On July 9th, 1962 the United States launched a Thor rocket armed with a W49 thermonuclear warhead to an altitude of nearly two hundred and fifty miles and detonated it.  It took thirteen minutes for the missile to reach its predesignated altitude before the 1.45 megaton explosion illuminated the night sky for hundreds of miles in every direction.  The missile, designated Starfish Prime, remains the biggest bomb ever detonated in space to this day.

Scientists were poised to study the effects of radiation at high altitudes on Johnston Island below.  Twenty-seven smaller rockets were launched alongside Starfish Prime to measure the effects of the detonation, but none of them, nor the scientists involved, were prepared for what would occur as a result of the explosion.

In the near vacuum of space, free electrons were hurled from the explosion in every direction and faced no atmospheric impedance.  Instead, they formed a brief, but powerful, electromagnetic pulse that caused power outages and other electrical issues on the Hawaiian Islands, nearly a thousand miles away.  At least six satellites orbiting near the explosion were lost despite the distance seeming so insurmountable that the U.S. government hadn’t even considered the likelihood of such damage occurring.   Scientists had discovered that high altitude detonations of nuclear weapons could disrupt the flow of electricity in devices thousands of miles away from the point of detonation.  Starfish Prime was not just a nuclear weapon, it was a weaponized EMP.

In the scope of threats to our way of life, few things should be more concerning than the prospect of a foreign nation using this method to cripple the infrastructure of the United States.  If a 1.45 megaton bomb could knock out electronics a thousand miles away, imagine what a warhead the size of the Soviet Tsar Bomba would do if detonated in low orbit above us.  Its 50 megaton yield would render the entire U.S. power grid a thing of the past.  Cars wouldn’t start.  Phones wouldn’t work.  The blackout would be all encompassing and permanent.

The threat of an EMP being detonated above us isn’t only a Russian one.  According to Dr. William Graham, who served as a science advisor to President Reagan and was a member of the Department of Defense’s Science Board, the threat could easily come from North Korea or Iran.

Unlike strategic nuclear strikes that require elaborate targeting systems and rocket technology that is beyond the reach of these unfriendly nations, an EMP strike would only need to reach high altitude airspace above the U.S.  According to Graham, an EMP delivering nuclear warhead could be fired from a simple container ship onboard platforms as simple and common as Scud missiles.  In July of 2014, ISIS claimed that even they currently have one captured Scud missile in their possession.  North Korea’s missile program, laughable as it may seem, could feasibly deliver the payload effectively if launched from a disguised naval vessel as well.

In 2008, a federal commission assigned to study EMPs and their possible damage to the infrastructure of the United States concluded that an attack on the American power grid could result in killing a whopping ninety percent of Americans over a twelve-month span.  Our growing dependence on technology for things like communication, transporting goods, and extending the shelf life of supplies would result in Americans starving in the dark.  The real damage would likely be self-inflicted as people grew desperate and started fighting amongst themselves.  To a large extent, a single EMP detonation could wipe the United States, as we know it, off the map.

The same EMP commission that determined potential casualty figures also reported that both Russia and China have “considered limited nuclear-attack options that, unlike their Cold War plans, employ EMP as the primary or sole means of attack.”